1. Field of the Invention
The present invention relates to image interpolation in an electronic device.
2. Description of the Related Art
A zoom function of a camera shortens a distance to an object being recorded. The zoom of an optical lens directly changes a focal length. However, the zoom of an optical lens is not suitable for a portable electronic device such as mobile phone, which is miniaturized and lightened. Hence, a digital zoom technique which increases an image resolution by interpolating an input image of the camera is more appropriate for the electronic device. Various image interpolation algorithms are applied to mobile cameras according to the related art.
A common algorithm applied to the mobile device according to the related art is a classical algorithm using linear combination, such as bilinear interpolation and bicubic interpolation. However, research has produced other algorithms including a least square estimation frequently applied to recent signal processing or communication, or adaptive directional image interpolation algorithm which features good interpolation performance in an edge region which is a high frequency component sensitive to human eyes. Frequency-domain image interpolation methods include Projection On Convex Set (POCS) interpolation including a wavelet image noise removal scheme.
However, it is hard to apply the methods according to the related art to the mobile electronic device because of limited hardware performance. In other words, because of the limited hardware performance in mobile electronic devices, it is difficult to apply the state-of-the-art technologies. Consequently, in a mobile environment, the use of an algorithm which does not require considerable computation or memory capacity is preferred. As a result, the digital zoom according to the related art is subject to abrupt jaggies (e.g., jagged diagonal edges) on the edges or blurring according to the image magnification.
Therefore a need exists for an apparatus and a method for enhancing digital zoom performance.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present invention.